Aftertale
by Guardian Alpha
Summary: It's been a good many years since Frisk freed the monsters from the underground. She is beginning High School and adjusting to life on the surface with her family. Things are going great until a new kid appears in her class. Arin, a loner, trouble magnet, compulsive liar who doesn't seem to have any friends. What will happen when a dark secret from the past rears its ugly head?
1. Meetings Human!

Aftertale  
Chapter 1: Meetings Human!

Disclaimer: I do not own Undertale or any of the characters involved except Arin.

It was a beautiful, sunny day in the city. A young teenage girl was walking down the street with an arm full of books. The child had long brown hair and was wearing a blue and purple striped shirt with blue shorts, black tights, and brown shoes. Beside the girl was a larger figure, a woman, but she had white fur all over her body and she was wearing a button up pink shirt and black pants, a pair of glasses rested on her snout.

"Are you ready for your first day of High School Frisk?" The goat woman asked.

Frisk nodded.

"Well, I hope you make lots of friends,"

Frisk looked up at the goat woman and smiled. A figure rushed past them, blowing a strong gust of wind at them. Frisk tried to catch a glimpse but the figure was already a few yards away, all she really saw was it was a boy her age with dark red hair and wearing a denim jacket with a bag slung over his shoulder.

"Sorry!" The figure called back.

"Really, the nerve of some people, rushing down the sidewalk without looking out for other people," Toriel said with a huff.

Frisk pulled on Toriel's sleeve and nodded toward the school down the road.

"You're right, if we don't hurry we'll both be late," She said.

Toriel led Frisk down the street to the school where the two parted ways, Toriel went to teach her math class while Frisk split off to head to her locker. As she arrived she noticed a figure down the hallway, a red-haired boy with a denim jacket. She knew it was the one who ran past her and Toriel earlier. He was surrounded by three larger students.

"Come on Arin, what do you have today?" One of them asked as he slammed his fist into his open hand.

"Please Charlie, it's all I have," Arin told him as he clutched a brown paper bag.

"Hand it over," Charlie grabbed the bag and shoved Arin away.

He took a look inside the bag and frowned, "A peanut butter sandwich? That's it!" He threw the bag down and the sandwich spilled out onto the floor.

Frisk watched the scene play out quietly. The trio began to beat on Arin eventually forcing him to the ground, when they had, had their fill they walked away, stomping on his sandwich as they went. Frisk waited a little before rushing over to see if Arin was ok. She saw he was pretty beaten up with bruises and a bloodied lip, she offered a hand to help him up and taking him to the nurse's office.

"Thanks," he said as he took it and stood, "You're Frisk right? That new kid who brought all the monsters with her?"

Frisk nodded.

"Wow, you're famous around here, you know that?"

Frisk shook her head, she indicated that they should go see the nurse, but Arin seemed oblivious to her signing.

"Don't talk much do you? Well, I guess it doesn't matter, the name's Arin," He put his hand out. Frisk shook her head and tried to indicate they needed to go to the nurse's office again.

"Human!" A voice called from the other end of the hall.

A tall skeleton approached Frisk and Arin, he wore a blue half-dome on his upper legs, a white chestpiece and a red scarf around his neck bones. He was carrying a math book under one arm.

"Whoa, a Skeleton," Arin said in surprise.

"Yes, I am the Great Papyrus, who are you?"

"My name's Arin, Frisk was just helping me up after I fell and dropped my bag," Arin extended his hand before Frisk got a chance to correct him, and Papyrus took it.

"Well, you should be more careful, though I doubt you'd ever be as graceful on your feet as I, The Great Papyrus,"

He looked down and noticed the smashed sandwich on the floor.

"Was that your lunch?" He asked.

"Yeah, before I dropped it anyway,"

"Allow me to make you some spaghetti for lunch! I should have some left over from my bowl, we can split it,"

"No, that's alright, I'll find something," Arin said with a dismissive smile.

"Are you sure?"

Frisk looked between the two as they talked showing a little concern, she knew what had happened, but didn't want to embarrass Arin in front of Papyrus by saying it.

"Yeah, I'm positive, thanks for the offer though, anyway I better get to class, see you guys later!"

Arin took off down the hall after he scooped up the sandwich and bag and threw them away.

"He sure is a nice guy, what do you think about him Human?"

Frisk nodded, still wondering why Arin lied. The bell rang drawing their attention.

"Come on Human, we need to get to class," Papyrus took Frisk's hand and led her to the classroom.

When they arrived they noticed Arin sitting in the back with his head on his desk and his arms hiding his face.

"Is that Arin?" Papyrus asked her.

She nodded.

"I didn't realize he was in class with us,"

Toriel entered the room as another bell sounded, "Alright my students, please be seated, some of you may have noticed a new student in our class today, Arin,"

Arin looked up at the sound of his name. Toriel jolted slightly at the sight of bruised face, his lip had stopped bleeding and he seemed to be a little cleaner than when Frisk had left him the hallway.

"Would you come up and introduce yourself please?"

Arin nodded as he stood and walked up to the front of the room. Now that he was standing in full view Frisk noticed his dark red shirt under his jacket, the dark blue pants he wore, and the black boots on his feet.

"My name is Arin, I've actually been here at the school for most of this year, I just got transferred to this class because I wasn't doing so well in my other one," Arin said with a slight bow.

"Well, I hope you excel here," Toriel said with a smile, trying to play off the slight lisp he had from his bruised lip.

"Thanks Mrs. Toriel," Arin returned to his desk and class began.

Frisk noticed that he never really paid attention to the lecture, didn't take any notes, and more or less just slept through class it looked like. After class Frisk approached Toriel's desk and asked about Arin.

"Well, he was right when he said he wasn't doing so well in his other class, the teacher there said he just slept through all of his classes and didn't do well on the tests, he was supposed to be a year ahead of you and Papyrus, but he was dropped down because they knew he wouldn't make the finals,"

Frisk nodded, and walked over to Arin's desk where a faint snoring sound could be heard. She put a hand on his arm and shook him slightly. He almost leapt out of the room as he jumped to his feet his head darting from side to side as if looking for an opponent.

"Oh, Frisk, hey," He said once he realized who it was.

Frisk told him it was time for lunch.

"Oh, good I'm starving," He said as he and Frisk walked to the lunchroom together.

Toriel noticed something about Arin, but couldn't quite put her finger on it, or her paw rather. Frisk and Arin entered the cafeteria where they saw Papyrus was sitting by himself, the two joined him and Papyrus smiled.

"Hello again Humans," Papyrus said.

"Hey Papyrus," Arin replied.

The trio was soon joined by monster kid, who was introduced to Arin and the group began to eat their respective lunches, except Arin. They all offered him some food, but he declined.

"So Papyrus, why do you always call Frisk 'Human'?"

"Well, when we were still in the underground, she was the first Human I ever met, and I didn't know her name as she didn't tell me, so I just called her Human, and, well, old habits are hard to break, even for someone as great as me,"

The bell rang and the group returned to class. Toriel lectured them for the rest of the day and as everyone was packing up their things Toriel grabbed Frisk's hand and led her out of the classroom to go home. A few minutes later they were leaving the school, they had to make sure Papyrus was doing alright. The two began to walk down the street when Frisk noticed Arin sitting on a street corner by himself. She tugged on Toriel's hand and she noticed what Frisk was looking at.

"Arin!" Toriel called.

He looked up, "Are you waiting on someone?" she called to him.

"Yeah, my dad should be here any minute!" He called back.

Frisk looked up at Toriel and shook her head. She explained what she knew about Arin, he didn't seem like the kind of person who would wait on his dad like this.

"Well, maybe he doesn't have a choice," Toriel told her.

Frisk shook her head and let go of Toriel's hand. She walked across the street to Arin and extended her hand. He looked up at her with confusion.

"I'm fine Frisk, I told you, I'm just waiting on… my dad,"

Frisk knelt down and wrapped her arms around him.

"Frisk? What are you doing?"

Frisk told him that she knew.

"What-what are you talking about?" Arin asked.

She explained, the lunch, the bullies, his sleeping through class. He was homeless with no parents.

"Is this true?" Toriel asked as she approached.

Arin looked down at his feet, "Yeah,"

Toriel put her paws to her mouth, "Arin… I had no idea,"

"It's fine, I've survived so far without them, I can keep going,"

"There's no need to, you're coming home with us," Toriel said.

"What? But, I couldn't," Arin looked away.

"Nonsense, you're coming home with us, and that's final," Toriel extended a paw and Frisk extended her hand again.

Arin thought about it for a moment before sighing and taking their limbs to help him up, but they didn't let go. They began to walk home and led Arin the whole way, never letting go of his hands. Arin felt something warm inside him that he'd never felt before.

" _Is this what it means to have a family?"_ He thought to himself.


	2. Practice

Aftertale  
Chapter 2: Practice

Disclaimer: I do not own Undertale or any of the characters involved except Arin.

Toriel opened the door of their home, leading Frisk and Arin inside. Once they crossed the threshold Frisk and Toriel let go of Arin's hands. He felt something leave him, but quickly pushed the thought aside.

"So Arin, welcome home," Toriel said with a smile as she put her arms up to indicate the house.

"Ah, Toriel, Frisk. You're home," A rumbling voice called from the other room.

Arin turned to see a large, male goat monster walk into the room. He was wearing a pink flower shirt and brown cargo shorts.

"Oh, we have company," He said with a smile, "Hello there, my name is Asgore,"

"You-you're the king of monsters!" Arin exclaimed.

"Well, yes, that is true, but these days I should probably be called the King of Flowers," He began to laugh loudly.

"Yes dear, " Toriel sighed.

"So, what's your name?" Asgore asked Arin.

"My name is Arin," He said with an affirmative tone in his voice.

"Arin is going to be staying with us for a while actually," Toriel told Asgore.

"Ah, well then make yourself at home. I hope you enjoy your time with us," Asgore said with a grin, he looked to Toriel who shook her head as if saying "We'll talk later,"

Frisk tugged on Arin's sleeve, drawing his attention.

"What's up Frisk?"

Frisk led him through the house and out a backdoor leaving Asgore and Toriel to discuss things.

"So, mind explaining what's happened?" Asgore asked his wife.

"Arin is an orphan, I had no idea until Frisk told me today. I thought we could take him in and help him get back on his feet. I'm afraid he's been getting picked on at school and he was beaten severely today,"

Asgore nodded as she explained, "I don't see any problems. We'll have to do some re-arranging but that shouldn't take much. I'll have Undyne and the Skeleton brothers come over and give us some help later,"

"Thank you for understanding,"

"It's not like I'm a heartless creature you know, I understand I made mistakes in the past but I'm trying to move past them," Asgore stated.

Toriel nodded and left him to go check on Frisk and Arin.

The pair had gone outside into the fenced off backyard. Frisk led Arin to the dead center and turned around and smiled at him.

"What's going on Frisk?" Arin asked.

Frisk held her hands in front of her chest and a large red heart appeared. Arin looked at her expectantly.

She frowned a little, confused.

"Were you going to show me something?" He asked.

Frisk tilted her head and held her hands up with her soul inside.

"My child," Toriel said from the doorway.

The two turned to her and she began to walk over. As she got close she put her paws on Frisk's hands and her soul disappeared.

"Not all humans can see souls my child," She explained.

"Souls?" Arin asked.

"Yes, Souls, the thing that makes up your essence. Your likes, dislikes, personality, hates, and loves. It's what makes you, you. Every living creature has a soul, monsters and some special humans are able to manifest and see their souls and those of others," Toriel explained.

"Is that what Frisk was trying to show me? Their soul?"

Toriel nodded.

"Is there a way I can be trained to see souls?" Arin asked.

Toriel went to say something but was cut off as Asgore walked out the back door.

"You want to see souls?" He asked Arin.

He turned to the larger man and nodded.

"Well, there's one of two ways you can learn to see souls: I can forcibly open your soul to the input of others, allowing you to see and manifest your soul and others, or you can train at it and open your soul on your own. The first option has a few dangers, but they are great. The second option is safer but might take some time,"

Toriel looked to Arin who contemplated for a minute. "I guess the safer route seems the better option, how do I begin?"

Asgore went to answer when the group heard a car door out in front of the house.

"I'll explain later, we should see who's here," Asgore said with a small smile.

He led the small family back inside and to the door where a few figures were waiting. Asgore opened it to reveal a fish-woman wearing a police uniform, and two skeletons: Papyrus and one shorter, broader skeleton.

"King Asgore, what can we do to help?" the fish woman asked.

"I didn't expect you to get here so early Undyne,"

"Well, I was just getting off my shift at work and…" Undyne stopped mid-sentence when she saw Arin in the back of the group.

"You!" She shouted.

"You know him?" Asgore asked.

"Yeah, I've seen him on patrol a few times, he always runs away when I get close," Undyne said.

"It's not a nice sight to see a police cruiser barreling toward you," Arin explained.

"I was just checking on you kid," Undyne told him a little aggressively, "I see some random human walking around town like he has nowhere to go and I feel obligated to check on him,"

Arin shook his head and tucked his hands into his pockets, "Whatever,"

Undyne glared at Arin before turning her gaze to Asgore and softening, "So, what's the deal Asgore?"

"Arin here is going to be living with us for a while, and we needed help re-arranging things," Asgore said putting a hand on Arin's back.

He jumped slightly as the large, furred hand touched him, but he quickly relaxed and that warm feeling returned.

" _What is this?"_ He thought to himself.

"Yeah, that shouldn't be too hard," Undyne said with a nod, she and the two skeletons entered the house and Asgore showed them to a room upstairs leaving Toriel, Frisk and Arin down in the entryway.

"I'm afraid I need to get to grading homework my children, feel free to explore Arin, just try to avoid getting in the way of the others," Toriel said.

Frisk nodded and Arin shrugged, "yeah, sure,"

Toriel reluctantly left them standing in the entryway as she went upstairs too. As soon as she was gone Frisk turned to Arin and tugged on his sleeve again, showing him into the living room. He noticed it was pretty basic: A large couch on one end was aimed perfectly at the TV and a large bay window gave them a lot of sunlight and a view of the street outside. Frisk walked over to the bay window and pulled a yellow flower in a pot off the sill and showed it to Arin.

"That's pretty cool Frisk," Arin said a little confused, it was just a flower…

"I'm not cool!" A voice barked at him.

Arin jumped and immediately started looking around.

"Down here,"

Arin eventually looked at the flower and realized it had a face in the middle of all the petals.

"A… talking flower? Are you some kind of monster too?" he asked.

"Yep, I'm Flowey, Flowey the Flower," It told him.

"Whoa…" he held his hand out to attempt to touch Flowey but then something happened suddenly.

Flowey leaned away from him, "You want to see something even 'cooler'?" Flowey asked

"Sure," Arin said in disbelief.

Flowey looked at Frisk who nodded and set him down. She had been working to rehabilitate Flowey so he wasn't as evil, she knew it would take time before he was even tolerably nice, he'd been especially good lately and she figured he was going to show Arin his pellets.

Arin stepped back a little before Flowey grinned evilly.

He looked at Arin and his eyes widened as he stared at Arin's chest. This made Arin feel a little weird before a sudden pain burst from near his heart.

"Ah!" He dropped to his knees and clutched at his chest.

Flowey's eyes had returned to normal as he watched Arin clutch his chest and gasp in pain. Frisk looked at Flowey with a disappointed look.

"Oh, I'm just getting started," Flowey said he summoned his pellets, "See kid, there's a thing you should know about monsters, we're not all as 'nice' as the King and his wife, some of us are just looking for a little _Friendship_ ," Flowey's voice took on an unsettling echo as he said the last word.

Arin looked up at him, sweat was beading down his forehead as he saw small pellets appear around Flowey, they spun in the air before stopping to aim at him. Frisk ran in front of Flowey and put her hands out to protect Arin.

"You're going to defend him?" Flowey asked.

Frisk nodded.

Flowey glared at Frisk for a moment before sighing and returning the pellets to his flower pot. She walked over and picked him up before putting him back on the sill and closing the large curtains, blocking out the light and Flowey from sight. Arin was catching his breath now as he stood up.

Frisk came over and looked at his chest, seeing what Flowey had done to him, his gasping eventually settled and he looked down at Frisk.

"What was that all about?" He asked.

Frisk shook her head and shrugged, she looked to the spot where she had sat Flowey back on the windowsill and then back to Arin, as if she was confused.

Arin just shook its head, "Whatever, I seem fine now so no harm done. Don't you think it's kind of dangerous keeping something like that in your house?"

Frisk looked back at Flowey again through the curtains and she remembered when she had to fight him in the Underground after he had absorbed all the monster's souls. She knew couldn't leave him down there alone and so had brought him to the surface.

Arin noticed Frisk was just staring off into the distance. He waved his hand in front of her face but got no response, he eventually shrugged and wandered upstairs, leaving Frisk in her daydream. He reached the top of the stairs and noticed it turned right into a small hallway that ended in a plain, white door, with doors to the left and right, on the left side he saw the open doorway, on the right was a sign that read "Frisk's room". He walked into the left doorway and stopped shock.

A bed was floating a few feet off the floor, a blue aura surrounding it. The bed eventually set back down on the floor in the corner of the room.

"Ah, Arin," Asgore's voice snapped Arin out of his fixation on the bed.

He looked away from the piece of furniture to see Undyne was putting a bookshelf up against the wall as the shorter, broader skeleton closed his eyes and looked toward the floor.

"We're almost done, just give us a few more minutes," Asgore said as he got down off a ladder, he'd been screwing in lightbulbs in the room as the others set up the rest of the furniture.

"No problem, so uh… Frisk introduced me to Flowey just now and he did something weird," Arin explained.

The whole group stopped and turned to look at him.

"What did that flower do kid?" The short skeleton asked.

"Well… I don't know exactly, he looked at my chest and I suddenly felt this immense pain, it went away and I feel fine now, but I just figured I'd want to check with you guys and see if that was normal,"

As Arin explained he watched the monster's faces grow worried, when he finished Asgore walked up to him and knelt down so they were seeing eye-to-eye.

"Arin," he said as he put his hand on the boy's shoulder, "I'd like to ask you something,"

"Sure,"

Asgore lifted his other hand and took his first hand from Arin's shoulder, he cupped them underneath where his heart would be on his chest and a gray heart appeared. Arin's eyes widened.

"So you can see it?" Asgore asked.

"Yes," Arin replied, "Is that?"

"My soul," Asgore told him before removing his hands and the heart returned inside his body.

"Now you try," Asgore told him as he stood.

Arin nodded and made the gesture himself, he felt a force, like something was trying to break free from his ribs, he relaxed and the pressure stopped, and a small, silver heart emerged from his chest.

The group gasped and Asgore lowered his head, casting his eyes in shadows.

"I'm sorry Arin, we were going to work to bring out your ability to see souls, but Flowey forced it out of you,"

"Was that it?" Arin asked as he pushed the heart back into his chest, "You said there were all these risks involved with that way,"

"There are, although I suppose it would be better if I explained: You see, Humans normally cannot see or manifest souls. It takes something to open their eyes; training or a monster. Monsters you see, can force the soul out of a human to harm them. This was the danger associated with forcing your ability. If you were to meet a monster that wanted to harm you they could force your soul out of your body, and as you experienced that can leave you with a severe sense of pain, while you are in pain you likely didn't see it but your soul emerged from your body, at that point a harmful monster could take the opportunity to kill you," Asgore finished explaining.

"Well, how do I defend myself if that happens now? I guess since I can see souls it's a little easier to fight back but… there's gotta be a way right?"

Asgore looked to the others who all looked away from his gaze.

"Normally, if you were a monster, there would be: Magic, but humans haven't shown the capability to cast magic since we've returned to the surface," Asgore explained.

"But, Humans could cast magic before?"

Asgore nodded, "the Humans of years ago gathered their most powerful spellcasters and wove the barrier that kept us sealed underground,"

Arin nodded now, "Well, maybe it's a dormant trait? We learned about them in school: A part of a being that didn't need to be used anymore but wasn't entirely wiped away. Since the humans didn't need to fight monsters anymore they didn't teach their kids how to do magic. This doesn't mean we can't, just that maybe we've forgotten how,"

Asgore thought about this for a moment, "I suppose you could be right, there's one way to check and make sure," he said.

"What would that way be?" Arin asked, having an idea of the answer already.

"We'll need to fight you," Asgore said as he summoned a red flame in his hand.


	3. Training Days

Aftertale  
Chapter 3: Training Days

Disclaimer: I do not own Undertale or any of the characters involved except Arin

Asgore doused the flame in his hand and Arin seemed a little disturbed.

"You have to fight me?" He asked

"Well, not so much fight you as train you," Asgore clarified.

"What does that mean?"

"If you're gonna learn magic kid, you need to see how it's done so you can figure it out for yourself. Everyone does it differently," The shorter skeleton brother chimed in.

"I'm sorry, we didn't get to meet, who are you?"

"Sans, Sans the skeleton, I'm Papyrus' older brother," Sans nodded towards Papyrus whose ever-present smile widened.

Arin nodded then turned back to Asgore, "So I just need to see how you guys all perform magic? That sounds easy enough,"

Asogre opened his mouth to say something, but then a thought crossed his mind, "I think it would be easier if we just showed you," he said after a moment of contemplative silence. "Why don't you head down to the backyard, we'll be there in a few minutes, we're just finishing up in here,"

Arin nodded and turned in the doorframe, heading down the stairs and out into the backyard. Frisk wasn't anywhere to be seen, he assumed she had slipped into her room while he was talking with Asgore. Once he was outside Arin went to the middle of the yard and cupped his hands under his heart again, his silver colored soul emerged once more.

" _I wonder if the colors have anything to do with it, I noticed Asogre's was gray,"_ He thought to himself.

He put his soul back inside his body and after a few minutes of waiting, which Arin passed by doing some stretches and short jogs, Asgore stepped out into the yard with Undyne and the Skeleton brothers.

"Are you ready Arin?" Asgore asked him.

"As I'll ever be,"

Asgore nodded and held out his hand, summoning the red flame again. He threw it into the air, and suddenly it exploded into a series of circling fireballs that rained down in the yard. Arin felt his soul exit his body. He looked up and saw that as the fireballs got closer to the ground the gaps between them widened, with a simple step to his right he stood between where two fireballs touched the grass a few yards on either side of him.

"That was an example of Red Magic, which we Dreemurs use," Asgore explained.

"Are the colors important?" Arin asked.

"You bet they are kid," Undyne stepped forward and with a gleam from her eye a pair of spears appeared point-first in the ground, "Pick it up,"

Arin nodded and drew one of the spears out, Undyne lifted her hand and with another gleam a dozen spears appeared in the air surrounding Arin.

"This is Green Magic!" Undyne shouted as she swiped her hand and the spears flew toward Arin. He lifted his spear and blocked the first one of the flying weapons, turning on the spot he blocked another, and another. Once all the spears were blocked the one he was holding disappeared.

Then he felt something weird happen to his soul, it felt… heavier. Suddenly Arin dropped prone, looking at Papyrus who was smiling as always holding his hand out.

"This is Blue Magic, there are two forms to it. I can make things heavier,"

Then Arin was suddenly lurched into the air a few feet off the ground.

"I can make things lighter and move them around," Sans stated.

Arin then slowly drifted to the ground and the feeling in his soul disappeared. An idea was forming in his head and he looked to Asgore.

"I noticed that my soul was similar in color to yours, does that mean anything?"

Asgore thought about it for a moment, "I suppose, if what research we had done on Human Souls discovered anything, it tells what your most dominant trait is,"

"Alright, what's Silver mean?"

"I don't know. We only had eight Human Souls and of them we only know the meanings of seven, and we have a guess at the eighth: Patience, Bravery, Integrity, Perseverance, Kindness, and Justice are the ones that are known, the eighth one we assume is Determination,"

"So you don't have any idea what my color means?"

"There are so many emotions and attributes Arin, it's hard to say which one yours represents the most,"

Arin nodded, a little crestfallen at the news.

"Well kid, the fastest way to finding out what your soul can do is to try," Sans told him.

"Practice does indeed make perfect," Papyrus added.

Arin nodded and clenched his fist. Holding it out in front of him toward Undyne he began to think of spears summoning like she had.

"What are you doing kid?" Undyne asked.

"Concen-trating," Arin gasped out.

"On what?"

"Summoning… spears,"

Undyne grinned before she couldn't hold back laughing which broke Arin's concentration.

"Spears are from Green Magic, you need to figure out what kind of magic you can use first," She continued to laugh.

Arin slumped to the ground, not knowing what to do next. "Is there anywhere we can go that might tell us something?"

Asgore started to shake his head when a thought crossed his mind. "Actually, there might be one place," He said.

Arin looked up excitedly, "Where?"

A few minutes later, Arin regretted asking that question. The group had traveled the few blocks into the city that led to the library. They were all currently sifting through history books looking through the era of the Human-Monster war.

"All I can find are reports of Humans using Red, Green, or Blue magic. Rarely there's a mention of another color but those seemed pretty unique," Asgore announced in a whisper to the others.

"I found something here about how Humans don't get magic like monsters do, it has to be taught to them and they can only learn Red, Green, or Blue," Sans added.

"That can't be right, I found a book here that says Humans get their own color of magic, it's just that Red, Blue and Green were the most common at the time,"

Arin was mindlessly flipping through pages when something caught his eye. Fanning through he found an image of a tall, broad-shouldered man with a white soul that seemed to reflect the lights above, the caption underneath read:

 _The Silver-Souled human, leader of the Human Defense Force. Not much is known about Humans with Silver Souls as only one has been found in all recorded history, and his name was lost in the burning of the records during the war._

"Guys, I found something," Arin said pointing at the caption. The others crowded around him and read through it for themselves.

"Defense force?" Undyne asked, "Like a Royal Guard?"

"Similar, yes," Asgore answered, "I wonder if his soul magic had anything to do with that,"

Arin went to say something when one of the librarians came over to their table and told the group they were closing for the evening.

"It is getting fairly late, why don't we head home and get some rest, we can continue this search tomorrow," Asgore said.

The group nodded and left the library, heading back to the Dreemur household Undyne, Papyrus, and Sans all piled into Undyne's car before saying good night to Asgore and Arin. Once they were gone the pair entered the house and each went their separate ways to bed. Arin entered his new room and collapsed onto the bed looking up at the ceiling.

"Man, this has been one crazy day," After he kicked off his shoes he leaned over and hit the light switch bathing his room in total darkness, shortly after, he was asleep. While he dreamed Arin saw visions of a battle field that was lit ablaze, legions of spears were being made out of thin air and launched into the horizon, one such volley came up from the horizon toward him, but in a second a hand appeared in front of him, his hand, and a large, silver-domed shield appeared and blocked the spears.


	4. Silver Shields

Aftertale  
Chapter 4: Silver Shields

Disclaimer: I do not own Undertale or any of the characters involved except for Arin

Arin awoke the next morning and rolled out of his bed. Walking down the stairs he smelled something that resonated in him, but he wasn't sure what it was. As he turned the last step and entered into the dining room he saw Toriel leaning into the over, a pan of eggs frying above her head on the stovetop. She produced a large pie and set it on the oven, closing the door she turned and saw Arin standing there and smiled.

"Oh, hello Arin, I hope you don't mind, I made a Butterscotch pie to celebrate your joining our little family,"

"Thanks, hey uh… have you seen Asgore?"

"I believe he's outside tending to his flowers," Toriel said as she considered his question.

"Alright, thanks Toriel," he waved a hand before stepping toward the back door.

Entered into the backyard Arin immediately saw Asgore's huge frame next to the house as he hummed to himself and watered some of his flowers.

"Hey, I wanted to talk to you about something," Arin said as he approached the large king.

"Good morning," Asgore responded.

"Sorry, good morning your majesty," Arin said with a slight nod of his head.

"No need for such formalities, you're a member of my family now," Asgore looked at Arin as he said this.

"Now, you wanted to discuss something?"

"Yeah, I had this dream last night. I think it had something to do with my magic,"

"Oh?"

"I was on a battlefield, it looked like a barrage of green magic users had launched a barrage of attacks and I lifted his hand to create a large barrier and blocked the attacks,"

Arin looked down at his palm as he finished, "I want to try it for real,"

"That's quite a jump, maybe it was just a dream?" Asgore asked him.

"No, it felt way too real to be just a dream," Arin told him as he clenched his hand into a fist.

"What do you want to do with this information?"

"I want to test it," Arin looked up at him with a determined look on his face.

Asgore considered his request before nodding, "Very well,"

He set his pail down before walking over a few feet and turning toward Arin.

"Are you ready?"

"Yeah," Arin lifted his hand up in front of him to await Asgore's attack.

"Very well, here we go," Asgore held up his hand the familiar red flame appeared. He threw it at Arin who swiped his hand through the air.

As he did this he felt his soul emerge from his body and a silver streak seemed to appear where his hand had moved. It blocked the fireball, causing it to disperse.

"So it wasn't just a dream," Asgore said to him as he walked back over.

"No, it doesn't look like it," Arin flexed his fingers by curling them in and out. The silver sheen was no longer present.

"I wanna keep training," he looked up to Asgore who smiled.

"Of course,"

The two spent the next half hour training in the back yard, Toriel came out and informed them lunch was ready, and was surprised to see Arin wielding magic. After an explanation of yesterday and today's events Toriel was happy to know Arin could defend himself and ordered the pair inside to get some food and rest.

Arin ate the meal with the Dreemurs, and as he sat at the table eating eggs he felt a warm feeling overcome him again. It was similar to what he'd felt when Toriel and Frisk had first walked him home.

" _So this is a family huh, not what I expected, but it'll do,"_ He thought to himself as he bit into a piece of toast.

"So, any plans for the weekend Frisk?" Asgore asked her.

She nodded and mentioned going to see Sans and Papyrus.

"That sounds like a fun time, maybe Arin should go with you?"

Frisk nodded and looked to Arin for confirmation.

"Uh… yeah, sure," he replied awkwardly.

An hour later Frisk and Arin had finished eating and were headed toward Sans' and Papyrus' house. Frisk was telling Arin about the two skeleton brothers and all of their antics back in the Underground.

"You're kidding? You went on a date with a skeleton?"

Frisk nodded and made a pose similar to Papyrus' "Cool Guy" pose before explaining. Arin burst out laughing as she finished. The two turned a corner and were immediately stopped as a red Ferrari pulled up beside them. The figure sitting in the seat was a gray-skinned, metallic looking man who looked at Frisk with a smile.

"Frisk! Darling! It's been too long!"

Arin looked confused as the figure got out of the car and approached Frisk. As they drew closer he realized the man was much taller than either he or Frisk.

"Who's your friend?"

Frisk introduced Arin to Mettaton and Mettaton to Arin.

"Pleasure to meet you Arin, I hope you're treating Frisk well,"

"Of course," Arin said

"Say, I was on my way to Papyrus' house to ask for a favor, where you two headed there as well?"

Frisk nodded.

"Would you like a ride?"

Frisk nodded again.

"Hop in!" Mettaton exclaimed with excitement as he stepped over the door and sat back down in the car.

Frisk and Arin both clamored into the backseat and Mettaton adjusted his mirror to see them both as they put on seat belts.

"Here we go," He said as he pushed on the gas.

The car took off and soon turned around before heading down the street. As they made their way to the skeleton's home Arin asked how Mettaton and Frisk knew each other. He'd seen Mettaton on TV and heard his music.

"Oh, that's a long story, "Mettaton explained off-handedly.

"Come on, I wanna hear it,"

"Well darling, if you must know, being famous wasn't anything strange to me…"

Mettaton's story continued on as the trio drove down the road toward the skeleton's house.

Meanwhile, in the deep underground.

A figure was sitting in a gray room, its face was distorted and pale. It sat in silence, perfectly still. As it sat there a strange thing appeared in the room. An orange button that simply read "Escape". It looked at it, the light reflecting off its face. It reached out and touched the button, and disappeared in a flash of white light.


	5. Secrets in the Dark

Aftertale  
Chapter 5: Secrets in the Dark

Disclaimer: I do not own Undertale or any of the characters involved except Arin

Frisk and Arin enjoyed the ride in Mettaton's car all the way to the Skeleton brother's house. When they pulled into the driveway Arin immediately noticed that despite it being late August the house has Christmas lights strewn from the rafters. When he asked Frisk about it she said that the Skeletons had lived in Snowdin before moving to the surface. The trio approached the front door and Frisk knocked.

It opened revealing the skeleton that Arin had met on his first day of High School: Papyrus.

"Nyah! Human! Mettaton! And… other human!" Papyrus shouted seeing them, "What are you all doing here?"

"Frisk wanted to stop by and hang out, and we met Mettaton on the way here," Arin told him.

He looked to Frisk and his cheek bones turned a light shade of red, "You want to hang out with me Human?"

Frisk nodded.

"Very well! Allow me to address Mettaton's need and then we shall hang out! Nyeh heh heh! In the meantime come in and make yourselves comfortable,"

Papyrus stepped aside allowing the trio to enter. Arin immediately noticed a few key features of the house: Firstly it was pretty bare, the doorway led into what he guessed was the living room based on the couch and tv, a single sock was lying on the floor near the couch, and a smaller skeleton was sitting on the couch with a remote in hand flipping through the channels on the tv. A doorway on the far right side of the room led into what Arin guessed was the kitchen based on what he could see, and on the opposite side was a set of stairs going up to a landing that had two doors on it. They were decorated but Arin wasn't able to see what was on them.

"Mettaton, we can discuss what you needed in the kitchen. The humans can stay here with Sans and watch some tv,"

Arin and Frisk nodded before walking over to Sans on the couch. Mettaton and Papyrus walked past and Sans' eyes followed them until they disappeared into the kitchen.

"Huh, didn't expect Mettaton to show up… how ya doin' kid?" He asked Frisk.

She explained that she was excited to hang out with him for the day and she'd brought Arin along so they could be properly introduced.

Sans looked at Arin before his eyes flittered down and then back up to his face. He locked eyes for a moment before extending his hand.

"Put 'er there kid,"

Arin was skeptical at first but reached out anyway and grabbed the bony hand, a loud farting noise filled the room as he went to grasp Sans' hand. A second later the skeleton began to laugh.

"Oldest trick in the book, gets 'em everytime," he said as he held up his hand and revealed a small whoopee cushion.

"Seriously?" Arin asked.

"C'mon kid, can't you take a joke?" Sans asked.

Arin sighed before a small smile appeared on his face.

"That'll do for a start I suppose, anyway, why don't you kids pop a squat and we'll watch some tv huh? You humans get so many more channels up here than we did in the Underground,"

The two kids sat down and began to watch Sans flick through channels attempting to find something good.

Meanwhile, the dark figure appeared in a flash of orange light in the middle of a crowded sidewalk. Monsters and humans walked past it without seeming to notice it. Looking around it was almost surprised to see humans _and_ monsters. In a rush it pushed past the passerby causing quite the scene, but eventually it retreated into a small alleyway where it cowered, trying to make sense of the situation.

" _Are you wondering why I brought you here?"_ A voice echoed in its mind.

The figure looked up and tried to find the source of the sound.

" _You won't see me around here, I'm not physically there at the moment,"_ The voice said.

"What… what do you want?" The figure asked, it's voice was cracking and raspy from dis-use.

" _I want something that was taken from me. Taken by a human child… I've given you your freedom so that you can find it for me… Do that and you'll be able to live freely forever,"_

"And… if I refuse?" The figure asked.

In a second it was back in the dark gray room deep in the underground. Its eyes widened, then it tried to run but only found nothing but an empty void.

" _This… this is what will happen if you refuse,"_ The voice said to him.

He nodded "I'll do it… tell me where the child is,"

" _Good… but first, you'll need to build up your strength… and to do that you'll need a new source of power,"_

"But… DETERMINATION… that's the strong source of power there is,"

" _No… it is not… I have found a much greater source of power,"_

"What?"

"… _Hatred,"_

In a flash the void was filled with seemed like liquid darkness. The black, ink-like substance washed over the figure and engulfed him. It felt like he was drowning, but almost as quickly as it appeared, it was gone, and the figure was once again in the alley where it had first heard the voice. It looked at its bony hands that had two holes in the palms, before clenching its fingers over them. Standing up straight the figure walked out of the alley and looked at the nearest figure: A cat-like humanoid monster.

"Hello there," it said kindly "Saw you dip into that alley a little bit ago, you alright?"

The figure reached out its hand and put it over the cat-man's face.

"Hey! What's the big i-" he was cut off as the figure drew out what seemed to be more of the liquid ink that had drowned it moments before. The cat-man dropped to his knees before collapsing, his face completely pale and his eyes blank.

The figure looked to his hand as the liquid drained into the hole in his palm before forming a small sphere. He smiled to himself with an evil looking grin and held out his hand, a large, skeletal beast's head appeared next to him and charged a black-colored energy in its mouth before firing it down the street.


End file.
